Page loads forever when using clusters with Nodejs / Expressjs - javascript

This is my application : app.js
/** Express **/
var express = require('express');
/** Create express application **/
var app = express();
/** Set application port **/
app.set('port', process.env.PORT || 3000);
/** Set application view engine**/
var handlebars = require('express-handlebars').create({
defaultLayout: 'main',
helpers: {
section: function(name, options){
if(!this._sections) this._sections = {};
this._sections[name] = options.fn(this);
return null;
},
parrot: function(options){
return options.fn(this) + ' <b> parrot </b>';
}
}
});
/*** Cluster Logger**/
app.use(function(req, res, next){
var cluster = require('cluster');
if(cluster.isWorker) console.log('CLUSTER: Worker %d received request.', cluster.worker.id);
next();
});
/** home page**/
app.get('/', function(req, res){
res.send('Welcome !!');
});
/** about page**/
app.get('/about', function(req, res){
res.send('About us!');
});
/** contact page **/
app.get('/contact', function(req, res){
res.send('contact us here');
});
// startServer in export/direct mode
function startServer(){
app.listen(app.get('port'), function(){
console.log('Parrot started in '+app.get('env')+' mode on http://localhost:'+
app.get('port')+
'; \n press Ctrl-C to terminate');
});
}
if(require.main === module){
startServer();
}else{
module.exports = startServer;
}
And this is parrot.js (with cluster include)
//import cluster
var cluster = require('cluster');
//startWorker
function startWorker(){
var worker = cluster.fork();
console.log('CLUSTER: Worker %d started', worker.id);
}
if(cluster.isMaster){
//in case the cluster is Master
require('os').cpus().forEach(function(){
startWorker();
});
cluster.on('disconnect', function(worker){
console.log('CLUSTER: Worker %d disconnected from the cluster', worker.id);
});
cluster.on('exit', function(worker, code, signal){
console.log('CLUSTER: Worker %d died with exit code %d (%s)', worker.id, code, signal);
startWorker();
});
}else{
//in case cluster.isWorker (not master), run app directly
require('./app.js')();
}
The problem, is that when I run node app.js, the app works just fine on http://localhost:3000 ... and the page works great in the browser.
When I run as a set of clusters (with node parrot.js), everything looks good in console:
CLUSTER: Worker 1 started
CLUSTER: Worker 2 started
Parrot started in development mode on http://localhost:3000;
press Ctrl-C to terminate
Parrot started in development mode on http://localhost:3000;
press Ctrl-C to terminate
But, the page loads forever and nothing shows on the browser? I don't know what's the problem here. Sorry for my language for I'm a Node.js newbie.
Thank you

I don't know exactly what's the problem, but when I tested on another computer (with a 32-bit OS), the example above worked without any problems.
This is my result now, when I visit a page in the browser :
CLUSTER: Worker 1 started
CLUSTER: Worker 2 started
Parrot started in development mode on http://localhost:3333;
press Ctrl-C to terminate
Parrot started in development mode on http://localhost:3333;
press Ctrl-C to terminate
CLUSTER: Worker 2 received request.
CLUSTER: Worker 2 received request.
Just in case clusters didn't work for you, test on a different machine.
Another question I have : I don't know why all requests are served by cluster worker 2 (the last one started), it seems like worker 1 doesn't receive any requests.
Thanks

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The code I use is exactly the same as in other projects I have done, so it makes no sense to me that this doesn't work now. -_-
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io = require('socket.io')(http,{
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node -v
v6.4.0
npm -v
5.3.0
npm list socket.io
socket.io#2.0.3
uname -m
armv6l
Edit: Updated messaging commands. Same issue. Also
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